What is the process for a prosthetic crown, from diagnosis to fitting?

12 May What is the process for a prosthetic crown, from diagnosis to fitting?

A prosthetic crown replaces damaged tooth structure when the cavity prevents stable restoration with composite material. A dentist may recommend one in cases of extensive decay, fractures, significant wear or following root canal treatment. This solution is often used on molars and premolars. Due to their function, these teeth bear the greatest chewing forces and therefore require robust mechanical reinforcement.

When is a crown better than a filling?

A dentist decides to fit a crown when the natural structure of the tooth does not provide sufficient strength. Typical situations include tissue damage caused by advanced tooth decay, mechanical trauma or long-term bruxism. A standard composite filling may simply fall out if the cavity is very extensive. Sometimes, the remaining natural tooth structure may also fracture under the pressure of biting.

Following endodontic treatment, the tooth requires special protection. The pulp-free tissue dries out, making it brittle and highly susceptible to longitudinal fractures. At the Smile Clinic, we make the decision on tooth preparation after assessing the thickness of the remaining tooth walls. Extensive damage means the tooth is suitable for a prosthetic restoration, which distributes occlusal forces evenly.

What does the diagnostic process involve before a crown is fitted?

The first appointment always begins with a consultation and a thorough clinical examination of the mouth. The dentist takes a spot X-ray or requests a three-dimensional CT scan. This allows them to assess the condition of the root, the quality of the root canal filling and the general condition of the surrounding tissues. On this basis, the specialist draws up a detailed treatment plan and determines the extent of the future preparation.

The patient’s bite itself, as well as the alignment of adjacent and opposing teeth, is also assessed. Imaging tests rule out any potential medical contraindications to the placement of a permanent restoration. These include, amongst others, a tooth stump that is too short or active periodontitis. Any inflammation of the gums must be treated before the actual prosthetic procedure can begin.

How is a tooth prepared for a crown?

The preparation involves after grinding away 1 to 2 mm of the outer tooth structure across all planes. The procedure is carried out under local anaesthetic, which numbs the treatment area. The dentist removes some of the enamel and dentine to create sufficient space for the restoration material.

A special thin retraction cord is then placed in the gingival sulcus. This gently retracts the soft tissues and exposes the margins of the preparation. This step is essential for taking a precise silicone impression or performing an accurate intraoral scan. The prepared stump is immediately covered with a temporary restoration. This protects the pulp from thermal sensitivity and prevents unwanted tooth movement whilst awaiting the final restoration.

What materials are crowns made from?

Patients have a choice porcelain-fused-to-metal crowns and all-ceramic crowns, which differ in their construction and aesthetic properties. Models on a metal alloy substructure are characterised by high mechanical strength. Their main drawback, however, is the risk of a dark line appearing along the gum line, particularly in cases of thin soft tissue.

Versions made from zirconium oxide or lithium disilicate offer a significantly higher level of aesthetics. These materials mimic the translucency of natural enamel and do not cause grey discolouration. Zirconia also exhibits high resistance to fracture under masticatory forces. Provided that proper oral hygiene is maintained The lifespan of all-ceramic restorations often exceeds 15 years. The decision to use a particular material dental technician is based on an analysis of the patient’s anatomical conditions.

How is the crown finally fitted?

During the fitting appointment, the dentist places the finished crown onto the stump and checks that it fits securely. The crown’s contact with the adjacent teeth and its correct positioning in relation to the bite are also checked. Occasionally, a minor adjustment to the shape is required using rotary burs.

Once the new crown meets the technical requirements and aesthetic criteria, it is permanently cemented in place. The dentist applies a thin layer of specialised dental cement. Once the cement has set initially, any excess is removed from around the gums. The process is completed by polishing the junction with the tooth, which prevents the build-up of bacterial plaque.

How many appointments does it take to have a crown fitted?

The standard prosthetic procedure usually takes two to three visits to the dentist’s surgery. The first appointment involves preparing the teeth and taking impressions. The final appointment involves trying on the crown and cementing the finished crown in place. The interval between appointments depends on the prosthetic laboratory’s workload.

Modern CAD/CAM design systems significantly shorten this process. Clinics equipped with milling machines can prepare a restoration in a single appointment lasting around two hours. On the other hand, the timeline is extended if the tooth requires prior endodontic treatment. The need to insert a reinforcing crown-root inlay adds a further necessary appointment to the schedule.

What should you bear in mind before the procedure?

The decision to commence prosthetic restoration is always based on a detailed clinical and radiological assessment.

• A crown protects teeth that have been damaged by tooth decay and those that have been restored following root canal treatment.
• The grinding of natural tooth tissue is carried out under local anaesthesia.
• All-ceramic zirconia restorations offer excellent aesthetics and a predicted lifespan of over 15 years.
• Preparing the tooth and cementing the restoration takes between one and three appointments.

A prosthetic crown is the ideal solution for teeth that have undergone root canal treatment or have extensive cavities. The process involves precise diagnostic imaging, preparation of the tooth under anaesthetic, and the taking of impressions. All-ceramic restorations made from zirconia guarantee the highest aesthetic quality and a lifespan exceeding 15 years. The entire treatment usually takes between one and three appointments, culminating in the permanent cementation of the restoration, which restores full chewing function and the aesthetics of the smile.

FAQ

Can you eat straight away after a prosthetic crown has been fitted?

Once the crown has been permanently cemented in place, it is advisable to refrain from eating for about two hours to allow the cement to set completely. If anaesthesia has been used, it is advisable to wait until sensation has fully returned before eating, as this prevents you from accidentally biting your cheeks. You should avoid very hard foods immediately after your appointment.

How should you look after the hygiene of a tooth with a crown?

Oral hygiene for a prosthetic crown does not differ significantly from that for natural teeth and requires regular brushing and flossing. Particular attention should be paid to the area near the gums, where bacterial plaque most often accumulates. Using a water flosser helps to effectively clean hard-to-reach spaces between the crown and neighbouring teeth.

Can a dental crown become discoloured in the same way as natural enamel?

Modern all-ceramic and zirconia crowns are highly resistant to discolouration and do not change colour when exposed to coffee, tea or tobacco. Unlike natural enamel, ceramic does not become porous, which helps to maintain its original appearance for many years. It is worth bearing in mind, however, that the natural teeth next to them may darken, which over time will create a difference in the shade of your smile.

Can tooth decay develop under a dental crown?

Although the crown itself does not decay, the natural stump of the tooth hidden beneath it remains exposed to bacteria at the point where it meets the gum. A leak in the restoration or poor oral hygiene can lead to the development of secondary caries beneath the crown margin. Regular dental check-ups allow for the early detection of such problems and an assessment of the integrity of the cementation.